Opening the Pandora box...

Xpongebob · Mar 12, 2012

Hi Guys !
I'm back, after some time to think about what to do on my Cdo... And I decided to open this damn' engine, and see for myself what was to be done. Here it is :

So... To sum up, I got :

- A cracked crankcase, which seems marked by a broken connecting rod,
- 2 differents connecting rods,
- A cracked cylinder barrel,
- A Cylinder head with exhaust port to be rethreaded,

The only parts which seems in good shape are :

- the camshaft
- the tappets

So, I'm know consdering going fully Maney.... :roll:

See you guys !

-

Hobot · Mar 12, 2012

Gald its not my own viewing of a worn out engine. I sure want people to support Steve Maney's production but your engine ain't all that bad so salvageable for others on lesser expense accounts. The chip in barrel by the lifter is insignificant non issue to run as is. Crankcase cracked by a rod usually only hurts it in mere oil sealing area so likely also a simple repair. Maney cases are significantly heavier than factory so takes a bunch of other removals and replacements to make up for it in racer bikes. Might just think about Maney cyclinders in a bigger bore and all the fancy rod/piston/flywheel/crankshaft upgrades and keep the nice light factory cases, unless also re-doing the valve train to take over redline WOT, that could over whelm factory cases. Even so I'd still prefer factory cases beefed up like racers. Best wishes on enjoying your plotting and planning.

Dances with Shrapnel · Mar 12, 2012

I am with Hobot on this one. From what I can see from the pictures, this is all serviceable stuff. Steve Maney items are great but unless you are going to up the power and sustained revs (aka racing) what you have in front of you should work.

In the worst case you could sleeve the barrels. Cam followers may benefit from a grinding to clean them up. The cam is showing some wear. As for the connecting rods being different; as long as they are Norton I would just seee to it that the rods, pistons and crank are balanced.

Again, this is assuming you are going with a street tuning for mild use. Anything more than that you should consider replacing the cast iron flywheel with a steel one.

Xpongebob · Mar 13, 2012

Thx for advices !
I will continue dismantling before ordering anything.
But I'm wondering if a potential unbalance of the crankshaft due to the difference between connecting rods may have caused the cracks on the crankcase... What do you think ?

cjandme · Mar 13, 2012

I think that it threw a rod and then someone put it back together on the cheap replacing only what they had to instead of doing it right. Cj

Hobot · Mar 13, 2012

Unless a rod breaks *from something else*, then quite a bit of imbalance can be tolerated by the engine/cases, but would transmit Buzz through iso's from horizontal imbalance. I agree likely a blow up fixed up as best they could and reasonably so if just sane public use. But what the heck if thinking of a Maney engine then were talking handful of $1000's not just a new set of Jim's piston/rod kit. In my last 4th Trixie redo, I just stuck in a replacement rod, a pair of off the shelf 40+ pistons, put on another crank cheek and that was it for rather nice isolation all day long tested to find I didn't want to get off after 9+ hours getting to and fro. It took about 1000 miles iso bedding in then me diddling head steady to neutral position before I though I had won back a normal feeling Commando again.

Xpongebob · Mar 14, 2012

Oh, by the way, is it common for the Cdo to break a rod on normal use ?
I mean, should I suspect a misuse ? How could I tell if the other rod is not affected ?

Cheers

marinatlas · Mar 14, 2012

Hi Xavier, normally you could reuse your barrels , about the rods , the best way is to have them magnafluxed or x-rayed ( but not anybody have access to such tools!!), and no they normally do not break under normal use , even in racing , the weakest part of them are the bolts (have a look to pirate parts on Andover site , about conrod bolts) , I do not want to speak about D rods , it has been discussed many times with no real assessment, but if you want buy a new pair of rods , or if you have the cash , go for Jim Schmidt piston rods (I had done it, but not yet tried , the work in in progress........), have your camfollowers surfaced /ground by a good engine shop (must be parallel), but yes change your cases! keep us informed.........Pierre

Xpongebob · Mar 14, 2012

Okay Pierre !
Thx for the tip (Jim Schmidt). I'm busy working right nowa, but I'll continue my dismantling asap

See U

Webby03 · Mar 14, 2012

marinatlas said:
Hi Xavier, normally you could reuse your barrels , about the rods , the best way is to have them magnafluxed or x-rayed ( but not anybody have access to such tools!!),

The Rods are Alloy, therefore they cannot be magnafluxed (Magnetic Particle Inspection - magnetoscopie en français). The material needs to be magnetic. However you can perform a penetrant inspection (ressuage) this too will find surface defects. A good sensitivity 3 fluorescent inspection would do the job.
As for a radiographic inspection, this will rarely find small surface defects but would find manufacturing defects in the material such as porosity etc.

Xavier, if you do wish to reuse the rods give me a call, I can inspect them at work. I'm à Bordeaux till the 24th.

All the best

Webby

Hobot · Mar 14, 2012

Oh, by the way, is it common for the Cdo to break a rod on normal use ?

Rods don't break unless something lets go first, bolts or crank or pistons or bearings, be it the D type or not. Dye crack test, polish up aong axis then shot peen and cryo-temper and run with confidence. Bolts seats are an issue to not shave off silver so relieve area if needed. I'd most want to cryo-temper new set of fasteners for the longest term. A very few racers say they have broken rods on liter size engine or others into red zone, if that level of endurance relates to your needs.

The real worry is the cast iron flywheel to my mind.

Xpongebob · Mar 15, 2012

Hey webby ,
I though you were leaving Bordeaux this week. Wanna come and see the Cdo this w-e ? I'll try to take them apart so you can have a look at these. Thx for your help !

Bernhard · Mar 15, 2012

hobot said:
Oh, by the way, is it common for the Cdo to break a rod on normal use ?

Click to expand...

Rods don't break unless something lets go first, bolts or crank or pistons or bearings, be it the D type or not. Dye crack test, polish up aong axis then shot peen and cryo-temper and run with confidence. Bolts seats are an issue to not shave off silver so relieve area if needed. I'd most want to cryo-temper new set of fasteners for the longest term. A very few racers say they have broken rods on liter size engine or others into red zone, if that level of endurance relates to your needs.

The real worry is the cast iron flywheel to my mind.

ref; "Rods don't break unless something lets go first, bolts or crank or pistons or bearings,"

To cut a long story short, Oh YES they do!!!
They can, but only if no oil gets to the crank & big end bearings.
A good reason to keep changing your oil & filter.

Webby03 · Mar 15, 2012

Xpongebob said:
Hey webby ,
I though you were leaving Bordeaux this week. Wanna come and see the Cdo this w-e ? I'll try to take them apart so you can have a look at these. Thx for your help !

Why not?
I'm here for another week. I'll send you a texto tomorrow to let you know when I'm available.
In fact, I have a portable ressuage kit & UV lamp that I can take to your place, I could do the inspection à chez toi

Webby

Hobot · Mar 15, 2012

To cut a long story short, Oh YES they do!!!
They can, but only if no oil gets to the crank & big end bearings.

dud Dude, you just supported my statement, here its the oil supply fault first and Foremost, not the rod's fault at all. Don't sweat the rods, worry about Everything Else surrounding and supporting them. If rods involved in a blow up I'd be pensive to re-use them but again not d/t anything innately weak about Norton rods, just anything can be injured beyond reasonable design limits.

Xpongebob · Mar 15, 2012

I could do the inspection à chez toi

Excellent :lol:

Xpongebob · Mar 18, 2012

I've just finished the engine opening, and here are some pics of what I saw :

I don't know what to think of the camshaft wear, seems standard to me :